Thank you for the advice so far
I don't really have anyone who could stay with Bear while I'm at work - everyone is either working or at university.
As I'm a teacher I can usually be home by 4pm but that's still 8 hours he'll be left alone... I am considering having the operation done over the school holidays but that would still only be 2 weeks in which I can supervise him 24/7. I might try calling the vet/daycare near me to see if they could keep him during the day to watch him.
We have tried using an x-pen before but Bear learnt how to climb out of it (even quite a high pen - little rascal!) so I think he'd need to be totally confined in something with a roof/cover.
Thank you again! I really appreciate all the advice and details of past experiences.